The use of LED technology in surgical lamps is known. In such surgical lamps, the color temperature of light emitted from the lamp can be adjusted in a determined range for a better discriminability of different types of tissue. As a result, it is possible to distinguish different kinds of tissue.
A surgical lamp employing LED technology is known from EP-A-1722157, which describes an arrangement in which the color temperature of the emitted light is created by various weighting of light sources emitting different spectra. A variation of the color temperature is possible in a range between 3,500 K and 5,000 K. The information about the emitted color temperature exists in the control of the surgical lamp. When changing the color temperature, the light intensity of the lamp is kept almost constant. The illuminants of the surgical lamp and their control units are calibrated in such a manner that the target settings of the control concerning the color temperature are exactly transformed to the real values.
Electronic cameras are also known. In one known example of an electronic camera, the incident light is transformed to voltage signals by sensors (CCD or CMOS). For capturing colored images, the light is color specifically captured by different sensors, which results in a color specific voltage signal, respectively. When displaying an image of an electronically captured video sequence, it can be beneficial to conduct white balance to reproduce the displayed image or the displayed video sequence in realistic colors.
A surgical lighting system is known from DE-A-20 2007 007 054 in which a communication between a lamp body and a camera takes place by calibration values that are transmitted from the lamp body to the camera by means of a bus system. The calibration values are experimentally determined. By means of this data transfer, the camera can appropriately adjust its white balance parameters, wherein a color-true rendering of the depicted operating area is guaranteed. The image signals are transmitted to a control device of the camera, and at the signal output of the control device, the image signals can be taken off for image processing apparatuses or for a monitor. By adjusting the color temperature at the lamp body, an adjustment of the camera takes place during the transmission of the image signals to the image processing apparatus or to the monitor so that an image having a color true rendering emerges.